Medical Errors

Growing attention to severe consequences resulting from medical errors was generated in 2000 by the Institute of Medicine (IOM) report To Err is Human: Building a Safer Health System. Based on the two large studies and extrapolation to over 33.6 million admissions to the hospitals in the United States the IOM report concluded that between 44,000 and 98,000 Americans die each year as a result of medical errors and many more are seriously harmed. It was truly a startling revelation that more people die every year as a result of medical errors than from motor vehicle accidents, breast cancer or AIDS. In 2004 the Canadian Medical Association Journal published results from a landmark study on the incidence of adverse events among hospital patients in Canada. Dr. Baker and the study team randomly selected one teaching, one large community and two small community hospitals in five Canadian provinces and reviewed the total of 3,745 medical charts for non-psychiatric, non-obstetric adult patients. Physicians reviewed all of the positively screened charts to identify adverse events and determine if they were preventable. After adjustment for the sampling strategy, the overall rate of adverse events was 7.5 per 100 hospital admissions. Among the patients who experienced adverse events 36.9% of those events were judged to be preventable while death occurred in 20.8%. It was also estimated that 1,521 additional hospital days were associated with adverse events. By extrapolation, results of this study suggest that every year about 185,000 hospital admissions are associated with an adverse event and close to 70,000 of these adverse events are potentially preventable. Allowing for the differences in definitions and methods used, several retrospective studies carried out in Australia, the United States, Denmark, United Kingdom, New Zealand, and other countries around the world produced similar results. The results of these studies are summarized in the table below.